Parasitology: Filaria

Question 1

Answer 1

Filariae: Loa Loa (eye worm)

• Epi: W. Africa
• Vector: Chrysops (but no multiplication)
• Transmission:
  
  • L3 inoculated when fly bites
  • L1 larvae in peripheral blood
• Sx: Calabar swellings on eyes
• Dx: surgical removal of worms, Ivermectin, DEC, Albendazole
• Control: DEC prophylaxis, fly screens, etc..

Question 2

Answer 2

Filiriae: Dracunculus medinensis (Guinea worm)

• Transmission: female guinea worm spreads in body (limb) when host is in water -> pain -> release of cyclops
• Rx: Albendazole, Thiabendazole, moist bandage
• Control: clean drinking water

Question 3

Answer 3

Filiariae: Onchocerca volvulus (river blindness)

• Epi: W. Africa, Central & S. America
• Transmission: L3 larvae deposited when fly feeds
• Sx: main pathology due to microfilariae in skin (hanging groin, papular dermatitis, skin atrophy) & eye (blindness, sclerosing keratitis)
• Dx: bloodless skin snips

Question 4

Answer 4

Filiriae: Wolbachia

• Epi: Africa,
• Transmission: intracellularly infects invertebrates, Gram -ve bacteria
• Features: Onchocerca volvulus - Wolbachia shown to be main cause of inflammation; TLR-4 mediated
• Rx: Ivermectin (microfilarcidal), doxycycline (Wolbachia) and thus adult worms

Question 5

Answer 5

Filariae: Wuchereria bancrofti

• Epi: tropical countries
• Vector: mosquitos (Culex, Anopheles, Mansonia)
• Transmission: infection thru drinking water, MF in peripheral blood, L3 innoculated
• Sx: 1. elephantiasis & 2. hydrocoele (in men)
  
  • chyluria (milky urine)
• Dx: ICT card, thick blood film, membrane filter concentration
• Rx: DEC, albendazole (macrofilariacidal), Ivermectin, surgery
• Control: bednets, insect repellants, DEC fortified salt